PHP Source code Analysis of the Base64_encode encryption function

Analysis of Base64_encode Encryption law
If the remainder of the string bytes divided by 3 is 0, there is no "=" symbol after encryption, and if each contiguous 3 block of characters is the same, the adjacent 4 strings are the same after encryption, for example Base64_encode ("abcabc") = = "YWJJYWJJ"
If the remainder of the string bytes divided by 3 is 1, then there are two "=" symbols after encryption
If the remainder of the string bytes divided by 3 is 2, then there is a "=" symbol after encryption

Not to be continued

PHP Source code Analysis of the Base64_encode encryption function